North Carolina Wildlife Resources Commission Gordon S. Myers, Executive Director

Mailing Address: Inland Fisheries Division • 1721 Mail Service Center • Raleigh, NC 27699-1700

Telephone: (919) 707-0220 • Fax: (919) 707-0028

June 7, 2018 NCWRC FISH KILL INVESTIGATION REPORT

Dates: May 4–9, 2018 County: Bladen Waterbody: White Lake Extent: Entire lake Observations: Approximately 114,770 dead fish Type of Pickup: NCWRC transect sampling on 5/9/2018 to estimate total dead fish OBSERVATIONS At 1235 hours on May 4, 2018, NCWRC staff was notified of a fish kill in progress at White Lake. At 1335 hours, K. Rachels, District-4 Fisheries Biologist, arrived at White Lake and assessed water quality. Dead fish were observed at Langston's Motel Beach (South shoreline) and at White Lake Marina (North shoreline). At 1500 hours, NCWRC staff reported the fish kill to the NCDEQ Fayetteville Regional Office and asked if NCWRC assistance was needed to conduct an enumeration. Assistance was not requested May 4–7. NCWRC staff assessed water quality on May 7 and May 8; water quality samples indicated dissolved oxygen and pH were within the EPA's National Recommended Aquatic Life Criteria and sufficient to support freshwater aquatic life. On May 8, 2018 at approximately 1600 hours, NCDEQ requested the NCWRC conduct a formal enumeration of the fish kill. On May 9, 2018, NCWRC staff collected dead fish from six randomly-selected 100-meter shoreline transects and six randomly-selected lake transects. At least one fish was observed in distress on May 9. A total of 407-kg of dead fish were collected from sample transects. Expanding sampled fish densities to the entire lake, estimated loss was 41,179 fish. However, kill estimates derived from field sampling methodologies grossly underestimate the actual number of fish that died during the event. Removal of dead fish by residents, property owners, and Town of White Lake personnel occurred for a period of 5 days between the initial kill event and the NCDEQ request for the NCWRC to conduct an evaluation. Removals by the Town of White Lake alone totaled 73,591 fish (Figure A.8). It is impossible to estimate the extent of fish removed by residents, additional losses attributed to wildlife scavengers, and fish carcasses that resubmerged. Total hatchery production costs for the 114,770 fish from NCWRC transect sampling (Table 1) and removals by the Town of White Lake (Table 2) is $634,132. The total administrative cost of the NCWRC investigation was $6,257 (Tables 6–9).

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SAMPLING METHODS Shoreline sampling.—Using the vector random selection tool in QGIS 2.18, six 100-m shoreline transects were randomly selected from a pool of 78 potential 100-m transects (Figure 3). Two-man crews arrived at each site by boat, marked the 100-m transect using GPS and a measuring tape, and collected all fish within the transect. Fish collected from each transect were identified (Table 4); batch-weighed by genus; and with one site exception, enumerated by genus. For Site I, size composition from other shoreline sites was used to enumerate Yellow Perch Perca flavescens and Lepomis spp. All taxa that were counted were also measured to the nearest 1-inch (25 mm). Mean density (# fish/100-m) was estimated for Yellow Perch, sunfish (all Lepomis spp. and Enneacanthus sp.), Chain Pickerel Esox niger, Lake Chubsucker Erimyzon sucetta, Yellow Bullhead Ameiurus natalis, and Largemouth Bass Micropterus salmoides. The total shoreline length (7,764 m) was measured using satellite imagery in QGIS. Expansion to the entire shoreline was estimated by multiplying each taxa density (by 1-inch size group) by 77.64. Lake Sampling.—Using QGIS 2.18, 3,895 possible transects were established on an east-west axis with a gap width of 6-m. Six transects were randomly selected using the vector random selection tool (Figure 3). Each boat crew consisted of a netter and a boat operator. Boat operators navigated to within 5-m of shore at each starting point and traversed the lake in a straight line, navigating via GPS to within 5-m of the endpoint located on the opposite shore. Netters used a 3-m long net to collect all fish within the transect. Accounting for net reach and the width of the boat, transects were 8.5-m wide. Fish collected from each transect were identified, batch-weighed by genus, and enumerated by genus. Mean density (# fish/acre) was estimated for Yellow Perch, sunfish, Chain Pickerel, Lake Chubsucker, and Largemouth Bass. Lake acreage (1059 acres) was measured using satellite imagery in QGIS. Expansion to the entire shoreline was estimated by multiplying each taxa density (by 1-inch size group) by 1059. White Lake Removals.—Between May 4 and May 9, staff with the Town of White Lake removed fish from both the lake and the shoreline. Removed fish were temporarily deposited at the town's landfill. On May 9, these fish were loaded onto a rollback waste container for transportation to a permitted landfill (see Appendix A, Figures A.6–A.8). NCWRC staff measured the container (6.7-m x 2.7-m x 1.4-m) and estimated it was filled with fish to approximately 75% capacity. Six galvanized washtubs with a known volume of 0.08 yd3 were filled with fish and weighed. Mean weight per cubic yard of fish was estimated (438.6 kg) and expanded to the entire waste container (24.2 yd3). Fish in the waste container were extremely desiccated; an inflation factor of 0.64 was used to convert the estimated dry weight to live weight. The taxa composition and size composition of the waste container was assumed to be the same as the composition of NCWRC shoreline and lake sampling on May 9, 2018.

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Hatchery Production Costs.—Hatchery production costs were estimated using American Fisheries Society (AFS) guidelines (Southwick and Loftus 2017). Hatchery production costs are assessed per fish, and vary by species and size group (Appendix B). Trophy-sized fish are assessed by the pound (live weight) rather than per fish. Length-weight regression equations were developed using 2015 White Lake sampling data when available (Largemouth Bass, Yellow Perch, and sunfish), while equations from the literature (Carlander 1970) were used for species with insufficient local data (Chain Pickerel, Lake Chubsucker, Yellow Bullhead) to estimate live weight of trophy sized fish. RESULTS

Table 1.—Estimated fish kill totals at White Lake on the sixth day (May 9, 2018) after the initial kill was reported based on shoreline and lake sampling transects. Pounds express estimated live weight. Hatchery production cost based on AFS guidelines (see Appendix B).

Taxa Number Killed Pounds Hatchery

Production Cost

Yellow Perch 27,589 1,837 $91,833.48

Largemouth Bass 4,556 8,764 $70,857.77

Sunfish 7,742 2,305 $20,013.43

Chain Pickerel 338 441 $10,170.24

Lake Chubsucker 889 1,970 $34,343.77

Yellow Bullhead 65 33 $273.72

Total 41,179 15,349 $227,492.41

Table 2.—Estimated fish removals by Town of White Lake personnel between May 4 and May 9, 2018. Pounds express estimated live weight. Hatchery production cost based on AFS guidelines (see Appendix B).

Taxa Number Killed Pounds Hatchery

Production Cost

Yellow Perch 49,304 3,282 $164,115.53

Largemouth Bass 8,142 15,662 $126,629.87

Sunfish 13,836 4,119 $35,765.98

Chain Pickerel 604 788 $18,263.41

Lake Chubsucker 1,588 3,520 $61,375.73

Yellow Bullhead 116 59 $489.17

Total 73,591 27,430 $406,639.69

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Table 3.—Length-weight regression equations used to estimate individual live weight.

Taxa aLength-Weight Equation Source

Yellow Perch Log10Weight = -5.08 + 3.04(Log10Total Length) NCWRC-unpublished data

Largemouth Bass Log10Weight = -5.12 + 3.09(Log10Total Length) NCWRC-unpublished data

Sunfish Log10Weight = -5.39 + 3.30(Log10Total Length) NCWRC-unpublished data

Chain Pickerel Log10Weight = -5.49 + 3.10(Log10Standard Length) Carlander (1970)

Lake Chubsucker Log10Weight = -5.05 + 3.22(Log10Total Length) Carlander (1970)

Yellow Bullhead Log10Weight = -4.11 + 2.66(Log10Total Length) Carlander (1970) a Total length converted to standard length using conversion factor in Carlander (1970).

Table 4.—Fish species observed dead in shoreline and lake sample transects at White Lake, May 9, 2018.

Common Name Scientific Name

Largemouth Bass Micropterus salmoides Bluegill Lepomis macrochirus Redear Sunfish Lepomis microlophus Warmouth Lepomis gulosus Bluespotted Sunfish Enneacanthus gloriosus Chain Pickerel Esox niger Yellow Perch Perca flavescens Lake Chubsucker Erimyzon sucetta Yellow Bullhead Ameiurus natalis

Table 5.—Water quality characteristics at White Lake as measured by NCWRC field staff.

Date Time Site Latitude Longitude aDO

(mg/L)

aDO (% Sat)

aTemperature (°C)

bpH cTotal Alkalinity

(ppm)

5/4 1335 FFA Camp Beach 34.6373 -78.5074 8.8 102 22.7 9.0 -

5/7 0645 Langston's Motel Beach

34.6351 -78.4869 8.4 99 23.3 7.0 8

5/7 0720 WLK Marina 34.6552 -78.5054 8.0 96 24.3 7.5 0

5/8 0845 Mouth of White Lake Drain

34.6467 -78.5096 8.0 92 22.5 7.0 4

aMeasured using YSI Pro2030 meter bMeasured using LaMotte 3353-01 kit cMeasured using LaMotte Direct Reading Titrator

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Figure 1.—Estimated number of dead fish associated with the fish kill event at White Lake, by taxa. Error bars denote bootstrapped 90% confidence interval.

Figure 2.—Estimated hatchery production costs for taxa impacted by the White Lake fish kill. Error bars denote bootstrapped 90% confidence interval.

0

25,000

50,000

75,000

100,000

125,000

150,000

175,000

Yellow Perch Largemouth Bass Sunfish Chain Pickerel Lake Chubsucker Yellow Bullhead

Nu

mb

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f D

ead

Fis

h

$0

$100,000

$200,000

$300,000

$400,000

$500,000

Yellow Perch LargemouthBass

Sunfish Chain Pickerel LakeChubsucker

YellowBullhead

Hat

cher

y P

rod

uct

ion

Co

st

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Figure 3.—Randomly-selected shoreline and lake transects for fish kill enumeration at White Lake, May 9, 2018.

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NCWRC STAFF EXPENSES Table 6.—NCWRC staff time associated with the fish kill investigation at White Lake.

Personnel Hours Hourly Rate Total

701 18 $ 33.33 $ 599.98

712 10 $ 26.82 $ 268.20

734 87 $ 22.78 $ 1,981.69

744 23 $ 20.24 $ 465.63

732 12 $ 24.87 $ 298.41

742 12.5 $ 19.45 $ 243.13

614 7.5 $ 24.93 $ 186.95

314 9.5 $ 26.64 $ 253.04

344 9 $ 18.81 $ 169.29

Tech I 8 $ 20.50 $ 163.99

Tech I 10 $ 17.97 $ 179.70

Temp 8 $ 14.83 $ 118.64

Grand Total 189

$ 4,928.64

Table 7.—NCWRC vehicle use associated with the fish kill investigation at White Lake.

Personnel Vehicle Rate Miles Amount

701 Silverado $ 0.46 207 $ 95.22

734 Silverado $ 0.46 512 $ 235.52

732 Silverado $ 0.46 80 $ 36.80

614 F-150 $ 0.46 73 $ 33.58

744 F-150 $ 0.46 262 $ 120.52

314 F-150 $ 0.46 88 $ 40.48

344 F-150 $ 0.46 51 $ 23.46

742 F-250 $ 0.46 231 $ 106.26

Tech I F-250 $ 0.46 93 $ 42.78

712 Crown Vic $ 0.42 186 $ 78.12

Tech I Dump Truck $ 0.65 41 $ 26.65

Grand Total

1827 $ 839.39

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Table 8.—NCWRC boat use associated with the fish kill investigation at White Lake.

Boat Hours Rate Amount

Inland Fisheries 8 $ 5.00 $ 40.00

Inland Fisheries 5 $ 5.00 $ 25.00

Inland Fisheries 5 $ 5.00 $ 25.00

Enforcement 5 $ 5.00 $ 25.00

Grand Total 23

$ 115.00

Table 9.—Other direct NCWRC expenses associated with the fish kill investigation at White Lake.

Expense Amount

Boat Gas $ 58.20 Sampling Supplies $ 284.66 Safety Supplies $ 24.12 Cleaning Supplies $ 7.42 Grand Total $ 374.40

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APPENDIX A

Figure A.1.—Example White Lake fish kill investigation shoreline transect.

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Figure A.2.—Example White Lake fish kill investigation shoreline transect detail.

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Figure A.3.—White Lake fish kill identification and enumeration by NCWRC field staff.

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Figure A.4.—Sample of Largemouth Bass 2–7 lbs from White Lake shoreline transect I.

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Figure A.5.—Partial view of fish collected from White Lake shoreline transect I by NCWRC field staff.

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Figure A.6.—Partial view of fish removed by Town of White Lake personnel.

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Figure A.7.—Detail of fish removed by Town of White Lake personnel.

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Figure A.8.—Rollback waste container (total volume = 24-yd3) with dead fish removed by Town of White Lake personnel.

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APPENDIX B

Southwick, R. I., and A. J. Loftus, editors. 2017. Investigation and monetary values of fish and freshwater mollusk kills. American Fisheries Society, Special Publication 35, Bethesda, Maryland.

The hatchery costs listed below were excerpted from Southwick and Loftus (2017). Following the recommendations of the editors, the hatchery production costs were adjusted to account for inflation using the Producers Price Index rate change from January 2016 to April 2018 (0.09529). The cost indicated is cost-per-fish for each size group (inches), except the per pound cost for trophy-sized fish.

Size Cost

0-1 $0.45

1-2 $1.08

2-3 $1.15

3-4 $1.75

4-5 $2.14

5-6 $2.77

6-7 $3.91

7-8 $4.79

8-9 $5.83

9-10 $6.00

10-11 $6.00

11-12 $7.75

12-13 $7.75

per pound >13 $6.27

Yellow Perch

Size Cost

0-1 $0.01

1-2 $0.91

2-3 $1.24

3-4 $1.29

4-5 $1.69

5-6 $1.88

6-7 $3.32

7-8 $3.54

8-9 $4.28

9-10 $4.28

10-11 $6.88

11-12 $6.88

12-13 $8.10

13-14 $8.13

14-15 $13.00

15-16 $15.00

per pound >16 $6.64

Largemouth Bass

Size Cost

0-1 $0.01

1-2 $0.13

2-3 $0.59

3-4 $1.04

4-5 $3.00

5-6 $3.00

6-7 $5.33

7-8 $7.67

8-9 $12.00

9-10 $12.00

10-11 $12.00

11-12 $12.00

12-13 $17.00

13-14 $17.00

14-15 $25.00

15-16 $25.00

16-17 $25.00

17-18 $25.00

per pound >18 $19.28

Chain Pickerel

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Size Cost

0-1 $0.14

1-2 $0.40

2-3 $0.46

3-4 $0.60

4-5 $0.87

5-6 $1.49

6-7 $1.92

7-8 $2.21

8-9 $3.14

9-10 $3.14

10-11 $5.75

11-12 $5.75

per pound >12 $3.71

Sunfish

Size Cost

0-1 …

1-2 …

2-3 $0.70

3-4 $0.85

4-5 $1.00

5-6 $2.00

6-7 $2.88

7-8 $3.75

per pound >8 $15.88

Lake Chubsucker

Size Cost

0-2 $0.33

2-3 $0.66

3-4 $0.81

4-5 $1.01

5-6 $1.10

6-7 $2.16

7-8 $2.39

8-9 $3.05

9-10 $3.98

per pound >10 $6.29

Yellow Bullhead